A dispersion having a cationic zeta potential for use as a base coating on a sheet of paper or paperboard as a primer for a functional barrier top coating, wherein the composition comprises an anionic pigment containing mixture comprising one or more anionic pigments in an amount of at least about 20% dry weight of the mixture, and one or more polyamine-epihalohydrin cationic wet strength resin.

Methods for improving one or more surface properties of a sheet of paper or paperboard, which method comprises (a) coating at least one side of the sheet of paper or paperboard with a dispersion having a cationic zeta potential formed by combining (1) a mixture containing one or more anionic pigments with (2) one or more polyamine-epihalohydrin cationic wet strength resins at a coating weight of from about 0.1 g/m.sup.2 to about 20 g/m.sup.2; (b) drying the coated sheet of paper or paperboard; (c) applying a functional barrier top coating that resists one or more of the following: liquid water, water vapor, gas permeability, oil and grease, slip, and static or an anionic latex based pigment coating that imparts improved opacity, brightness, or printability. The invention also includes the dispersions as well as paper or paperboard coated with the dispersion.

Methods for improving one or more surface properties of a sheet of paper or paperboard, which method comprises (a) coating at least one side of the sheet of paper or paperboard with a dispersion having a cationic zeta potential formed by combining (1) a mixture containing one or more anionic pigments with (2) one or more polyamine-epihalohydrin cationic wet strength resins at a coating weight of from about 0.1 g/m.sup.2 to about 20 g/m.sup.2; (b) drying the coated sheet of paper or paperboard; (c) applying a functional barrier top coating that resists one or more of the following: liquid water, water vapor, gas permeability, oil and grease, slip, and static or an anionic latex based pigment coating that imparts improved opacity, brightness, or printability. The invention also includes the dispersions as well as paper or paperboard coated with the dispersion.

It is an object to provide a composite in which the adhesion between a sheet layer and a curable resin layer or a film layer is high, and which has high strength and high transparency. The present invention provides a composite wherein a curable resin layer or a film layer is laminated on the one or both surfaces of the sheet layer with a covering layer interposed therebetween, the sheet layer containing fine fibers with an average fiber width of 2 to 1000 nm.

It is an object to provide a composite in which the adhesion between a sheet layer and a curable resin layer or a film layer is high, and which has high strength and high transparency. The present invention provides a composite wherein a curable resin layer or a film layer is laminated on the one or both surfaces of the sheet layer with a covering layer interposed therebetween, the sheet layer containing fine fibers with an average fiber width of 2 to 1000 nm.

Exemplary embodiments provide an erasable medium having an overcoat layer on a photochromic layer to provide a non-adhesive surface for the erasable medium when exposed to high temperatures, wherein the overcoat layer can include a latex or a mixture of a latex and a wax.

The present disclosure provides a print medium, a printed article, and a method of printing. The print medium can include a thin paper substrate having weight ranging from 40 GSM to 150 GSM, and a pre-treatment coating applied to the thin paper substrate at a weight ranging from 0.3 GSM to 15 GSM. The pre-treatment coating can include from 10 wt % to 80 wt % of a fixer, from 3 wt % to 50 wt % of a latex polymer, and from 5 wt % to 50 wt % of a water holding agent.

The present disclosure provides a print medium, a printed article, and a method of printing. The print medium can include a thin paper substrate having weight ranging from 40 GSM to 150 GSM, and a pre-treatment coating applied to the thin paper substrate at a weight ranging from 0.3 GSM to 15 GSM. The pre-treatment coating can include from 10 wt % to 80 wt % of a fixer, from 3 wt % to 50 wt % of a latex polymer, and from 5 wt % to 50 wt % of a water holding agent.

A gas barrier laminate including a gas barrier layer and a sealing layer laminated on a substrate in this order, wherein the gas barrier layer is a layer formed by applying and heat-drying a coating solution containing a water-soluble polymer and at least one of a metal alkoxide represented by a general formula M(OR.sub.1).sub.n(where M is a metal element, R.sub.1 is an alkyl group, and n is the oxidation number of the metal element) and a hydrolyzate of the metal alkoxide, a content of the water-soluble polymer is 50 wt % or more relative to a total mass of a solid content in the coating solution, a total content of the metal alkoxide and the hydrolyzate thereof is 5 to 50 wt % relative to the total mass of the solid content in the coating solution, and the sealing layer contains an aqueous heat seal varnish.

A gas barrier laminate including a gas barrier layer and a sealing layer laminated on a substrate in this order, wherein the gas barrier layer is a layer formed by applying and heat-drying a coating solution containing a water-soluble polymer and at least one of a metal alkoxide represented by a general formula M(OR.sub.1).sub.n(where M is a metal element, R.sub.1 is an alkyl group, and n is the oxidation number of the metal element) and a hydrolyzate of the metal alkoxide, a content of the water-soluble polymer is 50 wt % or more relative to a total mass of a solid content in the coating solution, a total content of the metal alkoxide and the hydrolyzate thereof is 5 to 50 wt % relative to the total mass of the solid content in the coating solution, and the sealing layer contains an aqueous heat seal varnish.